Exercise and Mental Health
Jesse Oswald • May 15, 2024
Highlights
- Exercise has been shown to be a powerful drug against mental disorders
- Physical exercise induces its beneficiary effect through several mechanisms that involve growth factor production, mitochondrial biogenesis, and angiogenesis
- According to one of the most significant meta-analysis studies on mental health, exercise should be a primary tool for mental health preservation.
In our previous article, “Nutrition & Mental Health,” we looked into the transformative nature nutrition can have on brain metabolism and, by implication, mental health. According to the decades-old theory correlating metabolism and mental health disorders, abnormalities in cellular brain metabolism, specifically mitochondria function, result in abnormal behaviour in several physiological mechanisms that control our mood, including neurotransmitter release, hormone release, hormonal resistance, and premature brain cell death. The quality, timing, and amount of food we consume have been shown to either promote or deter these deleterious mechanisms and, as a result, cause our mental health to deteriorate or improve respectively. Food is, consequently, a significant driver of mental health. Exercise has also been shown to be an equally, if not more significant, contributor to mental health. In this article, we explore the mechanisms through which physical exercise can support brain metabolism and thus play a significant role in helping one overcome psychiatric disorders.
How Exercise Impacts Brain Function
Exercise impacts brain metabolism through various mechanisms. Here are the main ones involved:
- Blood delivery: Physical activity increases blood flow and oxygen delivery to the brain, which enhances the brain's energy metabolism. This increased blood flow also promotes the release of growth factors and neurotrophins, which support the growth and survival of neurons.
- Neurotransmitter production: Exercise also stimulates the production of neurotransmitters, such as dopamine and serotonin, which play a role in mood regulation and cognitive function. These neurotransmitters can improve mood, reduce stress, and enhance cognitive abilities.
- Growth factors: Furthermore, exercise has been shown to increase the production of brain-derived neurotrophic factor (BDNF), a protein that supports the growth and maintenance of neurons. BDNF promotes neuroplasticity, which is the brain's ability to adapt and change in response to new experiences and learning.
- Angiogenesis: Regular exercise has also been linked to forming new blood vessels in the brain, a process called angiogenesis. This increased vascularization improves blood flow and nutrient delivery to brain cells, supporting their overall function.
- Mitochondrial biogenesis: During exercise, the increased demand for energy triggers a process called mitochondrial biogenesis, which involves the creation of new mitochondria. This increase in mitochondrial density enhances the brain's ability to produce ATP, the energy currency of cells.
- Protein synthesis: Exercise also stimulates the production of proteins involved in mitochondrial function and maintenance. These proteins help optimize the efficiency of mitochondrial respiration and the electron transport chain, which are essential for generating ATP.
The Unique Role of Zone 2 Training
Out of all types of exercise, Zone 2 training holds a special place in brain metabolism and, thus, mental health. Before diving into why, let’s first closely examine the different types of exercise. The three main types of training include endurance base training (also known as Zone 2 training which involves continuous exercise at Zone 2), resistance training (lifting weights or using other means to apply muscle resistance), and interval training (alternating between different exercise intensities while doing some sort of cardio like running or cycling). Here’s how each type affects our brain function and emotional state:
- Improved mitochondrial function: Zone 2 training specifically targets and improves mitochondrial function. Mitochondria are the powerhouses of our cells and are responsible for producing energy. Enhancing mitochondrial function through Zone 2 training gives the brain a more efficient and sustained energy supply, improving cognitive function and overall brain health.
- Enhanced fat-burning efficiency: Zone 2 training promotes the utilization of fat as a fuel source during exercise. This can be beneficial for brain health as it helps maintain stable blood sugar levels and prevents spikes in insulin. Consistent fat-burning during exercise can also support healthy brain metabolism and reduce the risk of metabolic disorders that can negatively impact brain function.
- Increased secretion of growth factors: Zone 2 training stimulates the secretion of growth factors in the brain. These growth factors promote the growth of new blood vessels and cells in the brain, leading to improved memory, cognition, and overall brain health.
- Improved recovery capacity: Zone 2 training helps enhance the body's recovery capacity, allowing for faster recovery after intense bouts of exercise. This is important for brain health as it reduces the risk of overtraining and supports optimal cognitive function.
A Widely Studied Intervention
The mechanisms through which exercise affects brain metabolism and its benefits for mental health are widely recognized and substantiated by an incredible breadth of scientific research. The scientific validation covers various psychiatric disorders through large-scale epidemiological studies.
- Depression: Numerous studies have shown that exercise can effectively treat depression. For instance, a meta-analysis of 25 randomized controlled trials found that exercise significantly reduced depressive symptoms in individuals with major depressive disorder.
- Anxiety disorders: Exercise has been shown to reduce symptoms of anxiety disorders, such as generalized anxiety disorder and panic disorder. A systematic review and meta-analysis of 49 studies found that exercise interventions were associated with a significant reduction in anxiety symptoms.
- Post-traumatic stress disorder (PTSD): Exercise benefits individuals with PTSD. Research suggests that exercise can help reduce symptoms of PTSD, such as intrusive thoughts and hyperarousal, and improve overall well-being.
- Attention deficit hyperactivity disorder (ADHD): Exercise has been shown to affect individuals with ADHD positively. Studies have indicated that exercise can improve attention, executive function, and behavioural symptoms in children and adults with ADHD.
- Substance use disorders: Exercise can be a helpful adjunct to treatment for substance use disorders. Research suggests that exercise can reduce cravings, improve mood, and support overall recovery in individuals with substance use disorders.
The effectiveness of exercise on psychiatric disorders was also recently validated through a large-scale meta-analysis study encompassing an enormous amount of data points from 97 meta-reviews of 1,039 randomized controlled trials involving 128,119 participants.
Conclusion
In conclusion, the relationship between nutrition, exercise, and mental health is becoming increasingly evident as scientific research sheds light on these lifestyle factors' transformative impact on brain metabolism and overall well-being. Nutrition significantly influences brain function by affecting cellular metabolism, neurotransmitter release, and hormonal balance. Similarly, exercise exerts powerful effects on brain metabolism through increased blood flow, neurotransmitter production, growth factors, angiogenesis, mitochondrial biogenesis, and protein synthesis.
Among various exercise modalities, Zone 2 training is particularly beneficial for brain health due to its targeted improvement of mitochondrial function, enhanced fat-burning efficiency, increased secretion of growth factors, and improved recovery capacity. The substantial body of scientific research supporting the positive effects of exercise on mental health covers a wide range of psychiatric disorders, including depression, anxiety disorders, PTSD, ADHD, and substance use disorders.
Incorporating regular exercise and a balanced diet into our daily lives can significantly benefit mental health and cognitive function. These lifestyle choices can act as powerful tools to help individuals overcome psychiatric disorders and improve their overall well-being. As we continue to deepen our understanding of the intricate relationship between nutrition, exercise, and mental health, it becomes increasingly clear that promoting a healthy lifestyle benefits our physical health and is essential for nurturing a resilient and vibrant mind.
An Ounce of Prevention - Hyperion Health Blog
What is a Kinesiologist?
Highlights Healthcare expenses are skyrocketing, with consumers and employers facing the significant brunt. Identifying those likely to get sick is critical as our resource-strapped healthcare system should focus on those likely to become the most significant burden to the system. VO2 max is a crucial longevity indicator that can also accurately predict healthcare expenses. The rampant chronic disease epidemic and the resulting surge in medical expenses is one of the most dire problems of modern societies, probably only second to climate change. Healthcare inflation is on a meteoric rise, and for those with limited or no healthcare coverage, a medical emergency is the equivalent of personal bankruptcy. A dire problem for employers In the US, employers and consumers who face rising health insurance premiums and astronomical out-of-pocket medical expenses feel the brunt of rising healthcare costs. Such is the problem that even large, well-capitalized corporations choose to send employees overseas for specific medical procedures since the cost of traveling and treatment in a foreign country is lower than the cost of care in the US. Another startling example is the infamous "northern caravan," a term that describes people with diabetes in the northern states who travel to Canada to secure their insulin supply. According to McKinsey , a survey conducted among over 300 employers highlighted that the average increase in the cost of health benefits over the past three years has been within the range of 6 to 7 percent. This survey also indicated that any rate increases exceeding 4 to 5 percent were deemed unsustainable. Interestingly, 95 percent of the surveyed employers expressed willingness to contemplate reducing benefits if costs surged by 4 percent or more. The primary cost-control measures that these employers indicated they might explore included elevating the portion of premium costs covered by employees and a potential transition to high-deductible health plans. Why is Breath Analysis relevant? Vis-a-vis this problem, the early and accurate estimation of who will get sick and how much they will cost is as critical as the treatment itself. The reason is that no other method of accurately identifying at-risk populations exists; it helps focus our scarce prevention resources and attention on those most in need. Breath analysis, AKA VO2max or metabolic testing, is an assessment that reveals two key biomarkers that provide significant predictive value for one's likelihood of developing costly chronic conditions. These two biomarkers are VO2max and the Respiratory Exchange Ratio. In this article, we will dive into VO2max to understand why it's a critical reflection of our overall health and, consequently, a window into our future healthcare spend. What is VO2max? Let's start with the basics. What is VO2max? VO2 max is the maximum amount of oxygen the human body can absorb. It is measured in terms of milliliters of oxygen consumed per kilogram of body weight. The below formula below indicates how VO2max is calculated: The numerator indicates the volume of oxygen your heart, lungs, and cells can absorb, expressed in milliliters per minute. The denominator indicates the weight of the individual represented in kilograms.
Key points A total fat intake between 20-35% ensures sufficient intake of essential fatty acids and fat-soluble vitamins Omega-6 PUFAs are primarily found in vegetable oils, while omega-3 PUFAs are primarily found in fatty fish and fish oils Both omega-3 PUFAs and MUFAs have established benefits for cardiovascular disease TFAs are the only dietary lipids that have a strong positive relationship with cardiovascular disease Omega-3 PUFA supplementation increases the beneficial bacteria of the human microbiome Over the last three decades, there has been a great revolution against fat due to its suspected association with several nutritional health issues, especially cardiovascular disease. There was a tremendous amount of evidence that indicated dietary cholesterol and saturated fat as the main culprits of cardiovascular disease, thus morbidity and mortality. It was when all the low-fat and no-fat dairy products started to launch, promising even complete substitution of the cholesterol-lowering heart medication if these products were exclusively consumed. Let’s start from the beginning. Dietary fat intake can vary significantly and still meet energy and nutrient needs. International guidelines suggest a total fat intake between 20% and 35% of the daily caloric consumption. This range ensures sufficient intake of essential fatty acids and fat-soluble vitamins. Not only does the quantity of the ingested fat matter, but most importantly, its quality. Some dietary fats have beneficial effects, with a significant role in maintaining good health, while others may threaten it. Which are, after all, the dietary fats? Dietary fats is a rather heterogeneous group of organic compounds, including four main types of fat, which are elaborately described in the following sections of this article. Polyunsaturated fatty acids (PUFAs) Polyunsaturated fatty acids (PUFAs) have two or more carbon-carbon double bonds. Omega-6 PUFAs and omega-3 PUFAs are the main types of PUFAs and are classified according to the location of the first unsaturated bond (sixth and third carbon atom, respectively). Alpha-Linolenic acid (ALA), docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), and eicosapentaenoic acid (EPA) are the most important omega-3 PUFAs. ALA is an essential fatty acid that can only be obtained from diet and can be converted into EPA and then to DHA, but the rate of this conversion is finite, approximately 7.0%–21% for EPA and 0.01%–1% for DHA. In the same way, the most important omega-6 PUFAs are linoleic acid (LA) and arachidonic acid (ARA). LA is an essential fatty acid that, in order to give rise to ARA, needs to be ingested through the diet as the human body cannot synthesize it. The recommended intake for total PUFA ranges between 5% and 10% of the total energy intake, while a total omega-3 PUFA intake of 0.5%–2% and a total omega-6 PUFA intake of 2.5%-5% is suggested. A dietary ratio of omega−6/omega−3 PUFA is recommended to be 1:1–2:1 to balance their competing roles and achieve health benefits. Omega-6 and omega-3 PUFAs Omega-6 PUFAs, in the form of LA, are plentiful in most crop seeds and vegetable oils, such as canola, soybean, corn, and sunflower oils. In contrast to omega-6 PUFAs, omega-3 PUFAs are obtained from a limited range of dietary sources. Flax, chia, and perilla seeds are rich in ALA, with significant amounts also detected in green leafy vegetables. The consumption of fatty fish, such as salmon, sardines, tuna, trout, and herring, provides high amounts of EPA and DHA. Besides fish and their oils, small amounts of omega-3 PUFAs are also detected in red meat like beef, lamb, and mutton. All the above dietary sources provide EPA, DPA, DHA, LA, and ARA in different amounts, and their intake is necessary for normal physiological function. PUFAs play a critical role in many chronic diseases, affecting human cells by regulating inflammation, immune response, and angiogenesis. Omega-3 PUFAs’ role against hypertriglyceridemia has been clarified, and research indicates that systematically consuming oily fish can contribute to general heart protection. Supplementation with omega-3 PUFAs could potentially lower the risk of several cardiovascular outcomes, but the evidence is stronger for individuals with established coronary heart disease. Moreover, adequate EPA and DHA levels are necessary for brain anatomy, metabolism, and function. Although the mechanisms underlying omega-3 PUFAs' cardioprotective effects are still poorly understood, several studies have been conducted in this direction. Unfortunately, that does not hold true for their omega-6 counterparts, for which controversial emerging data tend to show anti-inflammatory behavior that needs to be further studied. Monounsaturated fatty acids (MUFAs) In contrast to PUFAs, monounsaturated fatty acids (MUFAs) are easily produced by the liver in response to the ingestion of carbohydrates. The main MUFA is oleic acid, found in plant sources, such as olive oil, olives, avocado, nuts, and seeds, while minimal amounts are also present in meat, eggs, and dairy products. Specific guidelines around MUFAs’ dietary consumption do not exist. Therefore, MUFAs are recommended to cover the remaining fat intake requirements to reach the total daily fat intake goal. A growing body of research shows that dietary MUFAs reduce or prevent the risk of metabolic syndrome, cardiovascular disease (CVD), and hypertension by positively affecting insulin sensitivity, blood lipid levels, and blood pressure, respectively. Moreover, olive oil contains several bioactive substances, possessing anti-tumor, anti-inflammatory, and antioxidant qualities. According to a meta-analysis, consuming olive oil was linked to a lower risk of developing any sort of cancer, especially breast cancer and cancer of the digestive system. Another study found that an isocaloric replacement of 5% of the energy from saturated fatty acids (SFAs) with plant MUFAs led to an 11% drop in cancer mortality over a 16-year follow-up period. Therefore, including MUFAs in the everyday diet offers multifaceted benefits in chronic disease prevention and management, including cancer and general health promotion. Saturated fatty acids (SFAs) Saturated fatty acids (SFAs) form a heterogeneous group of fatty acids that contain only carbon-to-carbon single bonds. Whole-fat dairy, (unprocessed) red meat, milk chocolate, coconut, and palm kernel oil are all SFA-rich foods. These fatty acids have distinct physical and chemical profiles and varying effects on serum lipids and lipoproteins. Stearic, palmitic, myristic, and lauric acids are the principal SFAs found in most natural human diets. Dietary practice and guidelines recommend limiting SFA intake to <10% of the total energy (E%), while the American Heart Association suggests an even lower intake of <7 E% because total saturated fat consumption and LDL-C levels are positively correlated. However, the role of SFAs in CVDs is quite complex, and the evidence is heterogeneous. In a recent study with a 10.6-year follow-up period, which included 195,658 participants, there was no proof that consuming SFAs was linked to developing CVD while replacing saturated fat with polyunsaturated fat was linked to an increased risk of CVD. Moreover, according to 6 systematic reviews and meta-analyses, cardiovascular outcomes and total mortality were not significantly impacted by substituting saturated fat with polyunsaturated fat. Even if these analyses were to be challenged, due to heterogenous evidence, the possible reduction in CVD risk associated with replacing SFAs with PUFAs in several studies may not necessarily be an outcome of SFAs’ negative effect but rather a potential positive benefit of PUFAs. Regarding SFAs' effect on different types of cancers, associations of their intake with an increased risk of prostate and breast cancer have been indicated. Conversely, a meta-analysis showed no link between SFA intake and a higher risk of colon cancer; similarly, consuming MUFAs, PUFAs, or total fat did not affect colon cancer risk. Hence, the role of SFA consumption in preventing, promoting, or having a neutral role in serious chronic diseases has not been fully elucidated yet. Trans fatty acids (TFAs) Trans fatty acids (TFAs) are created industrially by partially hydrogenating liquid plant oils or can be naturally derived from ruminant-based meat and dairy products. TFAs are highly found in commercial baked goods, biscuits, cakes, fried foods, etc. Guidelines regarding TFAs are stringent and limit TFA intake to <1% of energy or as low as possible. In 2015, the US Food and Drug Administration declared that industrial TFAs are no longer generally recognized as safe and should be eliminated from the food supply as their consumption is strongly linked to various CVD risk factors. Specifically, TFA intake raises triglycerides and increases inflammation, endothelial dysfunction, and hepatic fat synthesis, leading to a significantly increased risk of coronary heart disease (CHD). A meta-analysis suggested that increased TFA intake led to an increase in total and LDL-cholesterol and a decrease in HDL-cholesterol concentrations. Data also indicates that TFAs may influence carcinogenesis through inflammatory pathways, but the reported data are debatable. A recent study investigated the effects of all types of dietary fat intake on CVD risk. While PUFA, MUFA, and SFA intake were not linked to higher CVD risk, dietary TFA intake showed a strong association with CVD risk. Analysis indicated PUFA intake and CVD risk were inversely correlated, and the relative risk of CVD was reduced by 5% in studies with a 10-year follow-up. Dietary lipids and the human microbiome Dietary lipids also affect human microbiota composition. Studies have identified a close association between the human microbiome and metabolic diseases, including obesity and type 2 diabetes. Diets with a high omega-6 PUFA, SFA, and TFA intake increase the amount of many detrimental bacteria in the microbiome and reduce the amount of the beneficial ones, altering the microbiota composition and inducing inflammation via the secretion of pro-inflammatory cytokines. These bacteria may disrupt the gut barrier function, allowing lipopolysaccharides (LPS) translocation, which are bacterial toxins. This condition is linked to metabolic perturbations such as dyslipidemia, insulin resistance, non-alcoholic fatty liver disease (NAFLD), and CVD. On the contrary, omega-3 PUFA (EPA and DHA) supplementation increases beneficial bacteria and limits harmful ones, enhancing intestinal barrier functioning and preventing LPS translocation and its implications. Omega-3 PUFA supplementation has also been studied as a means of mental health disorders management, but the evidence is still controversial. A possible protective impact of fish consumption on depression has been suggested by various studies, as well as a possible protective effect of dietary PUFAs on moderate cognitive impairment. A recent review of meta-analyses indicated that omega-3 PUFA supplementation might have potential value in mental health disorders, but data credibility is still weak. Dietary lipids and obesity Last but not least, obesity and its management is another field that dietary lipids intake seems to impact with their mechanisms. A diet high in PUFA has been shown to lower the total mass of subcutaneous white adipose tissue (the predominant fat type in human bodies), reduce blood lipid levels, and improve insulin sensitivity. In a study comparing PUFA and MUFA isocaloric intake, PUFA was more advantageous and lowered visceral adiposity in patients with central obesity. By stimulating brown adipose tissue, which aids energy expenditure through its elevated thermogenic activity, omega-3 PUFAs seem to elicit these positive effects in fat tissue, thus being useful in preventing and/or managing obesity. Another related study compared PUFA to SFA overfeeding in dietary surplus conditions that aimed to increase weight by 3%. While SFA overfeeding led to weight gain, primarily through the expansion of the visceral adipose tissue, PUFA overfeeding also led to weight gain, but because of a greater expansion of lean tissue mass. To sum up, dietary fats are an essential part of the human diet with many important physiologic functions, including cell function, hormone production, energy, and nutrient absorption. Moreover, dietary fat consumption is associated with positive outcomes in regard to cardiovascular disease, metabolic syndrome, cancer, and depression. 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